1. Field of the Invention
The present invention relates to a receiving apparatus and a receiving method that are capable of receiving for example digital television broadcasts.
2. Description of the Related Art
Ground digital television broadcasts have started all over Japan. As the number of users of ground digital television broadcasts are rapidly increasing, television receivers and television receiving apparatus for ground digital television broadcasts are rapidly widespreading.
In a receiving apparatus for a ground digital television broadcast, a modulation signal having a predetermined frequency is selected from a radio wave of a ground digital television broadcast received through an antenna connected outside the receiving apparatus. The selected modulation signal is processed by for example a demodulation process. As a result, a transport stream (TS) is obtained. When necessary, the TS is descrambled. The descrambled TS is filtered and separated into for example a picture, a sound, and data. The separated picture, sound, and data are decoded and provided to the user.
Such a receiving apparatus for a ground digital television broadcast is described in “Digital Broadcasting Receiving Apparatus (translated title)”, Standard SRIB STD-B21, Association of Radio Industries and Businesses, Japan.
Unlike an analog television broadcast, in a ground digital television broadcast, a picture signal type including resolution, aspect ratio, and so forth can be flexibly changed on the basis of a broadcasting station, a channel, and a watching hour. Thus, in a television receiver and a television receiving apparatus for ground digital television broadcasts, it is necessary to dynamically follow changes of broadcast picture signal types.
Thus, a receiving apparatus of the related art changes resolutions, aspect ratios, and so forth based on information about a picture signal type contained in a sequence header of an MPEG-2 (Moving Picture Experts Group-2) video stream of which a TS received from a transmission facility has been decoded.
In addition, a television receiver and a television receiving apparatus for ground digital television broadcasts are provided with a picture processing circuit that improves a picture quality. The picture processing circuit performs an advanced picture process for a picture signal to improve the picture quality. The picture processing circuit performs a picture process including noise removal, resolution conversion, and frame interpolation for each picture signal based on preset information of each picture signal and each picture signal type contained in the foregoing sequence header.
A technology of improving a picture quality by performing a predetermined picture process for a decoded video stream is described in Japanese Patent Application Laid-Open No. 2005-184563.